diff --git a/homeassistant/components/overkiz/const.py b/homeassistant/components/overkiz/const.py
index f207fc305e0..bf9ca3b343f 100644
--- a/homeassistant/components/overkiz/const.py
+++ b/homeassistant/components/overkiz/const.py
@@ -70,6 +70,7 @@ OVERKIZ_DEVICE_TO_PLATFORM: dict[UIClass | UIWidget, Platform | None] = {
     UIWidget.ATLANTIC_PASS_APC_HEATING_AND_COOLING_ZONE: Platform.CLIMATE,  # widgetName, uiClass is HeatingSystem (not supported)
     UIWidget.ATLANTIC_PASS_APC_ZONE_CONTROL: Platform.CLIMATE,  # widgetName, uiClass is HeatingSystem (not supported)
     UIWidget.DOMESTIC_HOT_WATER_TANK: Platform.SWITCH,  # widgetName, uiClass is WaterHeatingSystem (not supported)
+    UIWidget.HITACHI_DHW: Platform.WATER_HEATER,  # widgetName, uiClass is HitachiHeatingSystem (not supported)
     UIWidget.MY_FOX_ALARM_CONTROLLER: Platform.ALARM_CONTROL_PANEL,  # widgetName, uiClass is Alarm (not supported)
     UIWidget.MY_FOX_SECURITY_CAMERA: Platform.SWITCH,  # widgetName, uiClass is Camera (not supported)
     UIWidget.RTD_INDOOR_SIREN: Platform.SWITCH,  # widgetName, uiClass is Siren (not supported)
diff --git a/homeassistant/components/overkiz/water_heater_entities/__init__.py b/homeassistant/components/overkiz/water_heater_entities/__init__.py
index e03585da56d..abf9db78116 100644
--- a/homeassistant/components/overkiz/water_heater_entities/__init__.py
+++ b/homeassistant/components/overkiz/water_heater_entities/__init__.py
@@ -2,7 +2,9 @@
 from pyoverkiz.enums.ui import UIWidget
 
 from .atlantic_pass_apc_dhw import AtlanticPassAPCDHW
+from .hitachi_dhw import HitachiDHW
 
 WIDGET_TO_WATER_HEATER_ENTITY = {
     UIWidget.ATLANTIC_PASS_APC_DHW: AtlanticPassAPCDHW,
+    UIWidget.HITACHI_DHW: HitachiDHW,
 }
diff --git a/homeassistant/components/overkiz/water_heater_entities/hitachi_dhw.py b/homeassistant/components/overkiz/water_heater_entities/hitachi_dhw.py
new file mode 100644
index 00000000000..fa8c128e0c1
--- /dev/null
+++ b/homeassistant/components/overkiz/water_heater_entities/hitachi_dhw.py
@@ -0,0 +1,101 @@
+"""Support for Hitachi DHW."""
+from __future__ import annotations
+
+from typing import Any, cast
+
+from pyoverkiz.enums import OverkizCommand, OverkizCommandParam, OverkizState
+
+from homeassistant.components.water_heater import (
+    STATE_HIGH_DEMAND,
+    WaterHeaterEntity,
+    WaterHeaterEntityFeature,
+)
+from homeassistant.const import (
+    ATTR_TEMPERATURE,
+    PRECISION_WHOLE,
+    STATE_OFF,
+    STATE_ON,
+    TEMP_CELSIUS,
+)
+
+from ..entity import OverkizEntity
+
+OVERKIZ_TO_OPERATION_MODE: dict[str, str] = {
+    OverkizCommandParam.STANDARD: STATE_ON,
+    OverkizCommandParam.HIGH_DEMAND: STATE_HIGH_DEMAND,
+    OverkizCommandParam.STOP: STATE_OFF,
+}
+
+OPERATION_MODE_TO_OVERKIZ = {v: k for k, v in OVERKIZ_TO_OPERATION_MODE.items()}
+
+
+class HitachiDHW(OverkizEntity, WaterHeaterEntity):
+    """Representation of Hitachi DHW."""
+
+    _attr_min_temp = 30.0
+    _attr_max_temp = 70.0
+    _attr_precision = PRECISION_WHOLE
+
+    _attr_temperature_unit = TEMP_CELSIUS
+    _attr_supported_features = (
+        WaterHeaterEntityFeature.TARGET_TEMPERATURE
+        | WaterHeaterEntityFeature.OPERATION_MODE
+    )
+    _attr_operation_list = [*OPERATION_MODE_TO_OVERKIZ]
+
+    @property
+    def current_temperature(self) -> float | None:
+        """Return the current temperature."""
+        current_temperature = self.device.states[OverkizState.CORE_DHW_TEMPERATURE]
+        if current_temperature:
+            return current_temperature.value_as_float
+        return None
+
+    @property
+    def target_temperature(self) -> float | None:
+        """Return the temperature we try to reach."""
+        target_temperature = self.device.states[
+            OverkizState.MODBUS_CONTROL_DHW_SETTING_TEMPERATURE
+        ]
+        if target_temperature:
+            return target_temperature.value_as_float
+        return None
+
+    async def async_set_temperature(self, **kwargs: Any) -> None:
+        """Set new target temperature."""
+        temperature = cast(float, kwargs.get(ATTR_TEMPERATURE))
+        await self.executor.async_execute_command(
+            OverkizCommand.SET_CONTROL_DHW_SETTING_TEMPERATURE, int(temperature)
+        )
+
+    @property
+    def current_operation(self) -> str | None:
+        """Return current operation ie. eco, electric, performance, ..."""
+        modbus_control = self.device.states[OverkizState.MODBUS_CONTROL_DHW]
+        if modbus_control and modbus_control.value_as_str == OverkizCommandParam.STOP:
+            return STATE_OFF
+
+        current_mode = self.device.states[OverkizState.MODBUS_DHW_MODE]
+        if current_mode and current_mode.value_as_str in OVERKIZ_TO_OPERATION_MODE:
+            return OVERKIZ_TO_OPERATION_MODE[current_mode.value_as_str]
+
+        return None
+
+    async def async_set_operation_mode(self, operation_mode: str) -> None:
+        """Set new target operation mode."""
+        # Turn water heater off
+        if operation_mode == OverkizCommandParam.OFF:
+            return await self.executor.async_execute_command(
+                OverkizCommand.SET_CONTROL_DHW, OverkizCommandParam.STOP
+            )
+
+        # Turn water heater on, when off
+        if self.current_operation == OverkizCommandParam.OFF:
+            await self.executor.async_execute_command(
+                OverkizCommand.SET_CONTROL_DHW, OverkizCommandParam.ON
+            )
+
+        # Change operation mode
+        await self.executor.async_execute_command(
+            OverkizCommand.SET_DHW_MODE, OPERATION_MODE_TO_OVERKIZ[operation_mode]
+        )